title: Social network diagnostics: a tool for monitoring group interventions.
abstract: BACKGROUND
  Many behavioral interventions designed to improve health outcomes are delivered in group settings. To date, however, group interventions have not been evaluated to determine if the groups generate interaction among members and how changes in group interaction may affect program outcomes at the individual or group level.
  
  
  METHODS
  This article presents a model and practical tool for monitoring how social ties and social structure are changing within the group during program implementation. The approach is based on social network analysis and has two phases: collecting network measurements at strategic intervention points to determine if group dynamics are evolving in ways anticipated by the intervention, and providing the results back to the group leader to guide implementation next steps. This process aims to initially increase network connectivity and ultimately accelerate the diffusion of desirable behaviors through the new network. This article presents the Social Network Diagnostic Tool and, as proof of concept, pilot data collected during the formative phase of a childhood obesity intervention.
  
  
  RESULTS
  The number of reported advice partners and discussion partners increased during program implementation. Density, the number of ties among people in the network expressed as a percentage of all possible ties, increased from 0.082 to 0.182 (p < 0.05) in the advice network, and from 0.027 to 0.055 (p > 0.05) in the discussion network.
  
  
  CONCLUSIONS
  The observed two-fold increase in network density represents a significant shift in advice partners over the intervention period. Using the Social Network Tool to empirically guide program activities of an obesity intervention was feasible.
authors.affiliation: Department of Social Sciences and Health Policy, Division of Public Health Sciences, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA. sgesell@wakehealth.edu.
authors.forename: Sabina B
authors.initials: SB
authors.lastname: Gesell
authors.forename: Shari L
authors.initials: SL
authors.lastname: Barkin
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Valente
mesh_terms: D000328:Adult; D005240:Feasibility Studies; D005260:Female; D006126:Group Processes; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D009765:Obesity / Q000517:prevention & control; D010865:Pilot Projects; D060756:Social Networking; D011795:Surveys and Questionnaires; D013714:Tennessee; D055815:Young Adult